Bald eagles return to the same nest year after year, relining it with grass each breeding season and otherwise making repairs by adding more sticks. That behavior makes it easy for birders to keep track of the breeding pairs, although the nests can become so heavy that eventually they crash to the ground. Chorvas said the nest opposite the lighthouse is one of four in the area; there’s also an active nest at Bristol Beach, near Tivoli Bays, also in Dutchess County, as well as ones near Glasco and along the Ashokan Reservoir. The birds inhabiting the area now are a mixture of migrants spending the winter here—Chorvas said the majority of bald eagles breed in Canada and Alaska—resident adult birds, who stay in the area year-round, and juveniles; bald eagles don’t begin to breed until they are five years old, so until then, the immature birds simply hang out. (They are easily mistaken for migrating golden eagles: the youngest birds are brown, becoming mottled with white as they mature, until they emerge into adulthood with the signature white head and tail.) Particularly because of this teenage cohort, “it’s not uncommon to see from 30 to 35 bald eagles gathered around open water on the river in winter,” Chorvas said.
As recently as 10 years ago, it was rare to spot a bald eagle in Ulster County. Once, they covered the continent: Back in the 1700s, ornithologists estimate North America had a population of up to 500,000 bald eagles, Chorvas said. The bald eagle narrowly escaped extinction, reduced to just 478 birds on the entire continent in the late 1950s and early 1960s. The primary culprit in its demise was the pesticide DDT, which the birds ingested in fish and caused their eggshells to thin, preventing the hatching of their young. Widespread shooting of the birds was another problem. “It has been shot so consistently by hunters and taxidermists, fishermen and farmers, that Congress, in 1940, was finally compelled to prohibit its persecution or destruction anywhere but in Alaska,” writes Peter Matthiessen in his classic “Wildlife in America.”
Except possibly for a few areas in the western part of the state, the bald eagle was extirpated from New York, according to Chorvas. Its recovery in the Hudson Valley dates back to the 1970s, after DDT had been banned and the New York State Department of Conservation transported and released 140 chicks hatched in Alaska. Since the lifespan of a bald eagle is 30 years, that first generation of relocated bald eagles, all of which were banded by the DEC, have likely passed away, although some of their progeny may still be around. In 2007, the bald eagle had recovered sufficiently to be taken off the endangered species list. Chorvas said there are approximately 5,000 birds in the lower 48 states today, including 500 breeding pairs in New York; many more bald eagles inhabit Canada and Alaska.
Throughout the year, I often see them while walking my dog at Kingston Point or Sleightsburgh, at the mouth of the Rondout Creek. Two weeks ago, I tightened the leash of my Chihuahua-mix as three massively sized juveniles soared low over the trees at Kingston Point; in the summer, I’ve seen them perched on the rocks at the mouth of the creek, where they sometimes snatch a fish caught by a heron. Chorvas said the birds are opportunistic eaters, feasting not only on fish and smaller birds but also carrion. Common mergansers particularly attract bald eagles, and small mammals are also fair game, he said.
The bald eagle’s preference for carrion led Benjamin Franklin to denigrate it as “a bird of bad moral character” that “does not get his living honestly.” But those of us who find our river shore excursions immeasurably enriched by bald eagle sightings would doubtless agree with Matthiessen’s assessment: “White-headed and austere on a solitary tree, or flapping and sailing, stiff-winged and spread-fingered, over southern waterways or northern river deltas, inland river swamps or outer beaches, coursing the nation in summer and winter from the Columbia to the Merrimack, from the Everglades to the Yukon, the bald eagle is magnificent.” It was incredibly cold out at the lighthouse last Saturday morning, but I think most of the shivering observers (including a couple who drove all the way from New Jersey just for the privilege) would agree that the sighting of the white head poised near the top of that tall, distant white pine was definitely worth the price of discomfort.
